A nurse is tasked with administering digoxin to a child weighing 66 lb. How many mL should be given if the dosage is 12mcg/kg/day?

To calculate the appropriate dosage of digoxin for the child, the weight of the child in kilograms must first be determined. Since the child weighs 66 lb, it is necessary to convert this weight into kilograms, keeping in mind that 1 lb is equivalent to approximately 0.454 kg.

The conversion is performed as follows:

66 lb × 0.454 kg/lb = approximately 30 kg.

Next, the prescribed dosage of digoxin is 12 mcg/kg/day. To find the total daily dosage for the child:

30 kg × 12 mcg/kg/day = 360 mcg/day.

If the concentration of the digoxin solution is given (for example, if it were 100 mcg/mL), this total daily dosage needs to be divided by the concentration to find out how many mL should be administered.

Continuing with the example of a concentration of 100 mcg/mL:

360 mcg/day ÷ 100 mcg/mL = 3.6 mL.

Choosing 3.6 mL is correct because it reflects the accurate dosage calculation based on the child's weight and the prescribed medication guidelines. This application of weight-based dosing is critical in pediatric pharmacology to ensure the